Abstract 207P
Background
PET-CT is a surrogate marker of microvascular invasion and G3 differentiation. In patients with Hepatocellular carcinoma outside the Milan and UCSF criteria for liver transplantation (LT), 18-FDG accumulation is considered a risk factor if «downstaging» criteria are met or a contraindication in the case of a «sawtooth» (unstable) response curve according to mRECIST and AFP/PIVKA. The effectiveness of LT in patients with positive PET results is much lower than in patients with negative PET results. Lu RC et al. indicates that the rate of HCC recurrence after LT in patients with negative PET results is 3,6% and 54,3% in patients with positive PET results (p<0,001). 5-year disease-free survival of patients with PET-negative tumors comparable to that of the Milan criteria (86,2%), and outside the Milan criteria (81%), but it is significantly lower after LT of PET-positive HCC – 21%.
Methods
26 patients (HCC T2-3N0M0, BCLC-B) were performed baseline PET-CT examination (before «downstaging» therapy): 12 patients in the group of positive clinical outcome, 14 patients in the group of negative clinical outcome. 10 patients in the group of positive clinical outcome underwent liver transplantation. Nodes with SUVmax and SULpeak above the reference value of average accumulation in the mediastinal blood pool, calculated by the formula: 2*Mean + 2*SD, were considered as highly metabolically active.
Results
A statistically significant difference in the medians of Metabolic tumor volumes (MTV) with a fixed absolute threshold SUVmax=2,5 (Fixed Absolute MTV 2,5) was revealed. The median of Fixed Absolute MTV 2,5 in the group of negative clinical outcome was 199,06 ml (0;945,60), in the group of positive clinical outcome (underwent liver transplantation) was 10,15 ml (3,61;27,66) (p=0,03).
Conclusions
18F-FDG PET-CT and MTV is a strong independent prognostic factor in the evaluation of patients with HCC at high risk of early progression. This may be useful as a risk and prognostic factor in liver transplantation planning.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.